Over a period of time, the jawbone associated with missing teeth atrophies or is reabsorbed. This often leaves a condition in which there is poor quality and quantity of bone suitable for placement of dental implants. In these situations bone grafting is necessary to perform a successful operation. Bone grafting not only gives the opportunity to place implants of proper length and width, it also gives a chance to restore functionality and aesthetic appearance. There are several areas of the body which are suitable for attaining bone grafts. In the maxillofacial region, bone grafts can be taken from inside the mouth, in the area of the chin or third molar region or in the upper jaw behind the last tooth. In more extensive situations, a greater quantity of bone can be attained from the hip or the outer aspect of the tibia at the knee. Local anesthesia will be used to numb the area where the bone augmentation is needed (recipient site) as well as the area from where bone will be removed (donor site). The dentist makes an incision in the gum where the implant will be placed to determine how much and what type of bone is needed. Then an incision is cut in the gum below the lower front teeth to expose the chin bone. A block of bone will be removed from the chin along with any bone marrow. The block of bone that was removed from the chin will be anchored in place with titanium screws. In the case of smaller defects bone grafting materials (f.i: BioOss® synthetic materials) are sufficient. The bone graft will take about 6 to 12 months to heal before dental implants can be placed.
Sinus lift (Sinus Augmentation)
A sinus lift is done when there is not enough bone in the upper jaw, or the sinuses are too close to the jaw, for dental implants to be placed. The surgery adds bone to your upper jaw in the area of your molars and premolars to make it taller. The bone is added between your jaw and the maxillary sinuses, which are on either side of your nose. To make room for the bone, the sinus membrane has to be moved upward, or "lifted." The bone used in a sinus lift can come from your own body or synthetic materials can be used as well. If your own bone will be used in the sinus lift, it will be taken from other areas of your mouth or body. The surgeon cuts the gum tissue near the premolars and molars. When the tissue is raised the bone exposes. A small, oval window is opened in the bone. The membrane lining the sinus on the other side of the window separates your sinus from your jaw. This membrane is gently pushed up and away from your jaw. Granules of bone-graft material are then packed into the space where the sinus was. After a sinus lift, you need to wait several months for the bony material to harden and integrate with your jaw. If your own bone is used in the procedure, you may wait as few as six months. Once this happens, the implants will be placed.